1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Driver for TWL4030/6030 Pulse Width Modulator used as LED driver 4 * 5 * Copyright (C) 2012 Texas Instruments 6 * Author: Peter Ujfalusi <peter.ujfalusi@ti.com> 7 * 8 * This driver is a complete rewrite of the former pwm-twl6030.c authorded by: 9 * Hemanth V <hemanthv@ti.com> 10 */ 11 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/platform_device.h> 15 #include <linux/pwm.h> 16 #include <linux/mfd/twl.h> 17 #include <linux/slab.h> 18 19 /* 20 * This driver handles the PWM driven LED terminals of TWL4030 and TWL6030. 21 * To generate the signal on TWL4030: 22 * - LEDA uses PWMA 23 * - LEDB uses PWMB 24 * TWL6030 has one LED pin with dedicated LEDPWM 25 */ 26 27 #define TWL4030_LED_MAX 0x7f 28 #define TWL6030_LED_MAX 0xff 29 30 /* Registers, bits and macro for TWL4030 */ 31 #define TWL4030_LEDEN_REG 0x00 32 #define TWL4030_PWMA_REG 0x01 33 34 #define TWL4030_LEDXON (1 << 0) 35 #define TWL4030_LEDXPWM (1 << 4) 36 #define TWL4030_LED_PINS (TWL4030_LEDXON | TWL4030_LEDXPWM) 37 #define TWL4030_LED_TOGGLE(led, x) ((x) << (led)) 38 39 /* Register, bits and macro for TWL6030 */ 40 #define TWL6030_LED_PWM_CTRL1 0xf4 41 #define TWL6030_LED_PWM_CTRL2 0xf5 42 43 #define TWL6040_LED_MODE_HW 0x00 44 #define TWL6040_LED_MODE_ON 0x01 45 #define TWL6040_LED_MODE_OFF 0x02 46 #define TWL6040_LED_MODE_MASK 0x03 47 48 struct twl_pwmled_chip { 49 struct pwm_chip chip; 50 struct mutex mutex; 51 }; 52 53 static inline struct twl_pwmled_chip *to_twl(struct pwm_chip *chip) 54 { 55 return container_of(chip, struct twl_pwmled_chip, chip); 56 } 57 58 static int twl4030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm, 59 int duty_ns, int period_ns) 60 { 61 int duty_cycle = DIV_ROUND_UP(duty_ns * TWL4030_LED_MAX, period_ns) + 1; 62 u8 pwm_config[2] = { 1, 0 }; 63 int base, ret; 64 65 /* 66 * To configure the duty period: 67 * On-cycle is set to 1 (the minimum allowed value) 68 * The off time of 0 is not configurable, so the mapping is: 69 * 0 -> off cycle = 2, 70 * 1 -> off cycle = 2, 71 * 2 -> off cycle = 3, 72 * 126 - > off cycle 127, 73 * 127 - > off cycle 1 74 * When on cycle == off cycle the PWM will be always on 75 */ 76 if (duty_cycle == 1) 77 duty_cycle = 2; 78 else if (duty_cycle > TWL4030_LED_MAX) 79 duty_cycle = 1; 80 81 base = pwm->hwpwm * 2 + TWL4030_PWMA_REG; 82 83 pwm_config[1] = duty_cycle; 84 85 ret = twl_i2c_write(TWL4030_MODULE_LED, pwm_config, base, 2); 86 if (ret < 0) 87 dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label); 88 89 return ret; 90 } 91 92 static int twl4030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm) 93 { 94 struct twl_pwmled_chip *twl = to_twl(chip); 95 int ret; 96 u8 val; 97 98 mutex_lock(&twl->mutex); 99 ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG); 100 if (ret < 0) { 101 dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label); 102 goto out; 103 } 104 105 val |= TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS); 106 107 ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG); 108 if (ret < 0) 109 dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); 110 111 out: 112 mutex_unlock(&twl->mutex); 113 return ret; 114 } 115 116 static void twl4030_pwmled_disable(struct pwm_chip *chip, 117 struct pwm_device *pwm) 118 { 119 struct twl_pwmled_chip *twl = to_twl(chip); 120 int ret; 121 u8 val; 122 123 mutex_lock(&twl->mutex); 124 ret = twl_i2c_read_u8(TWL4030_MODULE_LED, &val, TWL4030_LEDEN_REG); 125 if (ret < 0) { 126 dev_err(chip->dev, "%s: Failed to read LEDEN\n", pwm->label); 127 goto out; 128 } 129 130 val &= ~TWL4030_LED_TOGGLE(pwm->hwpwm, TWL4030_LED_PINS); 131 132 ret = twl_i2c_write_u8(TWL4030_MODULE_LED, val, TWL4030_LEDEN_REG); 133 if (ret < 0) 134 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); 135 136 out: 137 mutex_unlock(&twl->mutex); 138 } 139 140 static int twl6030_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm, 141 int duty_ns, int period_ns) 142 { 143 int duty_cycle = (duty_ns * TWL6030_LED_MAX) / period_ns; 144 u8 on_time; 145 int ret; 146 147 on_time = duty_cycle & 0xff; 148 149 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, on_time, 150 TWL6030_LED_PWM_CTRL1); 151 if (ret < 0) 152 dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label); 153 154 return ret; 155 } 156 157 static int twl6030_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm) 158 { 159 struct twl_pwmled_chip *twl = to_twl(chip); 160 int ret; 161 u8 val; 162 163 mutex_lock(&twl->mutex); 164 ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); 165 if (ret < 0) { 166 dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", 167 pwm->label); 168 goto out; 169 } 170 171 val &= ~TWL6040_LED_MODE_MASK; 172 val |= TWL6040_LED_MODE_ON; 173 174 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); 175 if (ret < 0) 176 dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label); 177 178 out: 179 mutex_unlock(&twl->mutex); 180 return ret; 181 } 182 183 static void twl6030_pwmled_disable(struct pwm_chip *chip, 184 struct pwm_device *pwm) 185 { 186 struct twl_pwmled_chip *twl = to_twl(chip); 187 int ret; 188 u8 val; 189 190 mutex_lock(&twl->mutex); 191 ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); 192 if (ret < 0) { 193 dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", 194 pwm->label); 195 goto out; 196 } 197 198 val &= ~TWL6040_LED_MODE_MASK; 199 val |= TWL6040_LED_MODE_OFF; 200 201 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); 202 if (ret < 0) 203 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label); 204 205 out: 206 mutex_unlock(&twl->mutex); 207 } 208 209 static int twl6030_pwmled_request(struct pwm_chip *chip, struct pwm_device *pwm) 210 { 211 struct twl_pwmled_chip *twl = to_twl(chip); 212 int ret; 213 u8 val; 214 215 mutex_lock(&twl->mutex); 216 ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); 217 if (ret < 0) { 218 dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", 219 pwm->label); 220 goto out; 221 } 222 223 val &= ~TWL6040_LED_MODE_MASK; 224 val |= TWL6040_LED_MODE_OFF; 225 226 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); 227 if (ret < 0) 228 dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label); 229 230 out: 231 mutex_unlock(&twl->mutex); 232 return ret; 233 } 234 235 static void twl6030_pwmled_free(struct pwm_chip *chip, struct pwm_device *pwm) 236 { 237 struct twl_pwmled_chip *twl = to_twl(chip); 238 int ret; 239 u8 val; 240 241 mutex_lock(&twl->mutex); 242 ret = twl_i2c_read_u8(TWL6030_MODULE_ID1, &val, TWL6030_LED_PWM_CTRL2); 243 if (ret < 0) { 244 dev_err(chip->dev, "%s: Failed to read PWM_CTRL2\n", 245 pwm->label); 246 goto out; 247 } 248 249 val &= ~TWL6040_LED_MODE_MASK; 250 val |= TWL6040_LED_MODE_HW; 251 252 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_LED_PWM_CTRL2); 253 if (ret < 0) 254 dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label); 255 256 out: 257 mutex_unlock(&twl->mutex); 258 } 259 260 static const struct pwm_ops twl4030_pwmled_ops = { 261 .enable = twl4030_pwmled_enable, 262 .disable = twl4030_pwmled_disable, 263 .config = twl4030_pwmled_config, 264 .owner = THIS_MODULE, 265 }; 266 267 static const struct pwm_ops twl6030_pwmled_ops = { 268 .enable = twl6030_pwmled_enable, 269 .disable = twl6030_pwmled_disable, 270 .config = twl6030_pwmled_config, 271 .request = twl6030_pwmled_request, 272 .free = twl6030_pwmled_free, 273 .owner = THIS_MODULE, 274 }; 275 276 static int twl_pwmled_probe(struct platform_device *pdev) 277 { 278 struct twl_pwmled_chip *twl; 279 280 twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL); 281 if (!twl) 282 return -ENOMEM; 283 284 if (twl_class_is_4030()) { 285 twl->chip.ops = &twl4030_pwmled_ops; 286 twl->chip.npwm = 2; 287 } else { 288 twl->chip.ops = &twl6030_pwmled_ops; 289 twl->chip.npwm = 1; 290 } 291 292 twl->chip.dev = &pdev->dev; 293 294 mutex_init(&twl->mutex); 295 296 return devm_pwmchip_add(&pdev->dev, &twl->chip); 297 } 298 299 #ifdef CONFIG_OF 300 static const struct of_device_id twl_pwmled_of_match[] = { 301 { .compatible = "ti,twl4030-pwmled" }, 302 { .compatible = "ti,twl6030-pwmled" }, 303 { }, 304 }; 305 MODULE_DEVICE_TABLE(of, twl_pwmled_of_match); 306 #endif 307 308 static struct platform_driver twl_pwmled_driver = { 309 .driver = { 310 .name = "twl-pwmled", 311 .of_match_table = of_match_ptr(twl_pwmled_of_match), 312 }, 313 .probe = twl_pwmled_probe, 314 }; 315 module_platform_driver(twl_pwmled_driver); 316 317 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); 318 MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030 LED outputs"); 319 MODULE_ALIAS("platform:twl-pwmled"); 320 MODULE_LICENSE("GPL"); 321